U.S. patent number 7,766,480 [Application Number 12/505,346] was granted by the patent office on 2010-08-03 for gonio lens with geometric reference.
This patent grant is currently assigned to Ocular Instruments, Inc.. Invention is credited to Raymond D. Graham, Sungjun J. Hwang, Mark A. Latina.
United States Patent |
7,766,480 |
Graham , et al. |
August 3, 2010 |
Gonio lens with geometric reference
Abstract
A gonio lens is provided including a contact lens element and a
geometric reference member. The contact lens element has an optical
axis, a concave posterior contact surface to be placed in optical
contact with the cornea of a patient's eye, and an anterior
surface. The geometric reference member, such as a scale, is
provided near the concave posterior contact surface of the contact
lens element. The configuration and location of the geometric
reference member are chosen to provide an image of the geometric
reference member adjacent to an image of the periphery of the
anterior chamber of the eye of a patient within a field of view of
the contact lens element when the contact lens element is placed on
the eye of a patient. The two images are formed relative to each
other such that they are simultaneously in focus to permit visual
comparison between the two.
Inventors: |
Graham; Raymond D. (Renton,
WA), Hwang; Sungjun J. (Victor, NY), Latina; Mark A.
(North Andover, MA) |
Assignee: |
Ocular Instruments, Inc.
(Bellevue, WA)
|
Family
ID: |
42358746 |
Appl.
No.: |
12/505,346 |
Filed: |
July 17, 2009 |
Current U.S.
Class: |
351/219;
351/221 |
Current CPC
Class: |
A61B
3/117 (20130101) |
Current International
Class: |
A61B
3/00 (20060101); A61B 3/10 (20060101) |
Field of
Search: |
;351/219,221,205,246,247,160R,160H,159 ;606/4,6,18 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Boys-Smith, J.W., "Boys-Smith Pigment Gradation Laser Lens,"
.COPYRGT. 1984, Ocular Instruments, Inc., Bellevue, Wash., 3-page
brochure. cited by other.
|
Primary Examiner: Dang; Hung X
Attorney, Agent or Firm: Christensen O'Connor Johnson
Kindness PLLC
Claims
The embodiments of the invention in which an exclusive property or
privilege is claimed are defined as follows:
1. A gonio lens for use on an eye of a patient comprising: a
contact lens element having an optical axis, a concave posterior
contact surface and an anterior surface, said contact lens element
having a mirror associated therewith and offset from the optical
axis thereof, the mirror having a planar surface that is angled
away from the optical axis as the planar surface extends in an
anterior direction, and a geometric reference member provided near
the concave posterior contact surface, the configuration and
location of the geometric reference member being chosen to provide
an image of the geometric reference member adjacent to an image of
the periphery of the anterior chamber of the eye of a patient
within a field of view of the contact lens element when the concave
posterior contact surface of the contact lens element is in optical
contact with a cornea of the eye of the patient, the two images
being formed relative to each other such that they are
simultaneously in focus.
2. The gonio lens of claim 1, wherein the geometric reference
member is a scale.
3. The gonio lens of claim 2, wherein the scale includes linear
markings.
4. The gonio lens of claim 3, wherein the linear markings comprise
vertical bars that are horizontally arranged.
5. The gonio lens of claim 3, wherein the linear markings comprise
horizontal bars that are horizontally arranged.
6. The gonio lens of claim 2, wherein the scale includes circular
markings.
7. The gonio lens of claim 2, wherein the scale includes polar
markings.
8. The gonio lens of claim 1, wherein the geometric reference
member consists of a single marking.
9. The gonio lens of claim 8, wherein the single marking is a
bar.
10. The gonio lens of claim 1, wherein the geometric reference
member includes a rectangular grid.
11. The gonio lens of claim 1, wherein the geometric reference
member includes a polar grid.
12. The gonio lens of claim 1, wherein the geometric reference
member is applied over a background, the color of the geometric
reference member is chosen to be in contrast with the color of the
background.
13. The gonio lens of claim 12, wherein the background comprises
fluorescent material.
14. The gonio lens of claim 1, wherein the geometric reference
member comprises fluorescent material.
15. The gonio lens of claim 1, wherein the geometric reference
member is constructed as a removable component, which is removably
attached to the contact lens element.
16. The gonio lens of claim 15, wherein the geometric reference
member is constructed as a ring, which is removably attached to the
contact lens element.
17. A gonio lens for use on an eye of a patient, comprising: a
contact lens element having an optical axis, a concave posterior
contact surface and an anterior surface; and a geometric reference
member provided near the concave posterior contact surface, the
configuration and location of the geometric reference member being
chosen to provide an image of the geometric reference member
adjacent to an image of the periphery of the anterior chamber of
the eye of a patient within a field of view of the contact lens
element when the concave posterior contact surface of the contact
lens element is in optical contact with a cornea of the eye of the
patient, the two images being formed relative to each other such
that they are simultaneously in focus.
18. The gonio lens of claim 17, wherein the geometric reference
member comprises a scale.
19. The gonio lens of claim 17, wherein the geometric reference
member comprises fluorescent material.
20. The gonio lens of claim 17, wherein the geometric reference
member is constructed as a removable component, which is removably
attached to the contact lens element.
Description
FIELD OF THE INVENTION
The present invention relates to lenses utilized in the examination
and treatment of the eye and, more particularly, to lenses utilized
in viewing the periphery of the anterior chamber of the eye.
BACKGROUND
A lens utilized in connection with gonioscopy, i.e., the viewing of
the periphery of the anterior chamber of the eye, is known as a
gonio lens or gonioscope. A gonio lens generally includes a contact
lens element and one or more minors. The contact lens element has
an optical axis and a concave posterior contact surface that
conforms to the anterior surface of the cornea of an eye. The
contact lens element also has an anterior surface that is offset in
an anterior direction from the contact surface. At least one minor
is arranged with its planar surface angled away from the optical
axis of the contact lens element in an anterior direction. When the
contact lens element is positioned on the eye, the mirror(s)
reflect the light from the periphery of the anterior chamber of the
eye into the direction of the observer, typically via a microscope
for necessary magnification. The observer can thus study an image
of the periphery of the anterior chamber to assess, for example,
the iridocorneal angle, i.e., the angle formed by the cornea and
the iris of an eye, or the trabecular meshwork located around the
base of the cornea. For example, the observer can visually assess
any inflammation or structural defects in the trabecular meshwork
and related adjacent structures in the eye. As another example,
using a gonio lens that is configured for the dual purposes of
viewing and treating an eye, such as an iridotomy goniolaser lens
and a trabeculoplasty goniolaser lens (e.g., a Selective Laser
Trabeculoplasty lens or SLT lens), the observer may assess the
trabecular meshwork before, during, and after the treatment with
laser energy to thereby assess the efficacy of the treatment.
SUMMARY
This summary is provided to introduce a selection of concepts in a
simplified form that is further described below in the Detailed
Description. This summary is not intended to identify key features
of the claimed subject matter nor is it intended to be used as an
aid in determining the scope of the claimed subject matter.
It would be desirable for the observer of a gonio lens to be able
to make geometric assessment or measurements of the image of the
periphery of the anterior chamber of the eye. For example, the
observer may wish to determine the size or shape of any defects
visible in the image or the relative distance between two or more
points in the image. The present invention is directed to providing
a gonio lens that permits such geometric assessment and
measurements by the observer.
According to various exemplary embodiments of the present
invention, a gonio lens is provided including a contact lens
element, one or more mirrors, and a geometric reference member. The
contact lens element has an optical axis, a concave posterior
contact surface to be placed in optical contact with the cornea of
a patient's eye, and an anterior surface. At least one minor is
offset from the optical axis of the contact lens element and
includes a planar surface that is angled away from the optical axis
as the planar surface extends in an anterior direction. The
geometric reference member, such as a scale, is provided near the
concave posterior contact surface of the contact lens element. The
configuration and location of the geometric reference member are
chosen to provide an image of the geometric reference member
adjacent to an image of the periphery of the anterior chamber of
the eye of a patient within a field of view of the contact lens
element when the contact lens element is placed on the eye of a
patient. The two images are formed relative to each other such that
they are simultaneously in focus to permit visual comparison
between the two. Accordingly, the observer can readily determine
the size or shape of any artifacts in the image of the periphery of
the anterior chamber or the relative distance between two or more
points in such image.
In accordance with other embodiments of the present invention, a
gonio lens includes a contact lens element and a geometric
reference member as with the previously described embodiments, but
does not include any mirror. In operation, the light rays from the
periphery of the anterior chamber propagate directly toward the
observer. As with the previously described embodiments, the
observer can then compare the image of the periphery of the
anterior chamber relative to the image of the geometric reference
member, to thereby determine the size or shape of any artifacts in
the image of the periphery of the anterior chamber or the relative
distance between two or more points in the image.
The geometric reference member may be a scale including a series of
linear, circular, or polar markings. The geometric reference member
may also consist of a single marking, such as a bar. Further
alternatively, the geometric reference member may include a
rectangular grid or a polar grid. The specific configuration of a
geometric reference member may be chosen depending on the
particular type of gonio lens in which the geometric reference
member is applied.
In accordance with one aspect of the invention, the geometric
reference member is applied over a background, and the color of the
geometric reference member is chosen to be in contrast with the
color of the background. The background and/or the geometric
reference member may include fluorescent material so as to emit
light in a contrasting color relative to each other.
DESCRIPTION OF THE DRAWINGS
The foregoing aspects and many of the attendant advantages of this
invention will become more readily appreciated as the same become
better understood by reference to the following detailed
description, when taken in conjunction with the accompanying
drawings, wherein:
FIGS. 1A-1C are respective bottom view, cross-sectional view, and
perspective view of the gonio lens with geometric reference
constructed in accordance with an embodiment of the present
invention;
FIG. 2 is a longitudinal cross-sectional view of the gonio lens of
FIGS. 1A-1C, similar to the cross-sectional view of FIG. 1B, shown
in contact with the cornea of a patient's eye and illustrating the
optical path for viewing the periphery of the anterior chamber;
FIG. 3 schematically shows an image visible to the observer of the
gonio lens of FIG. 2;
FIGS. 4A and 4B are respective bottom view and cross-sectional view
of the gonio lens with geometric reference constructed in
accordance with another embodiment of the present invention;
FIG. 5 schematically shows an image visible to the observer of the
gonio lens of FIGS. 4A and 4B in contact with the cornea of a
patient's eye;
FIGS. 6A-6F illustrate six different embodiments of geometric
reference that may be used in accordance with the present
invention;
FIGS. 7A-7D schematically show an image visible to the observer of
the gonio lens incorporating the geometric references of FIGS.
6C-6F, respectively;
FIGS. 8A and 8B are respective bottom view and cross-sectional view
of the gonio lens with geometric reference constructed in
accordance with yet another embodiment of the present invention;
and
FIGS. 9A and 9B are respective bottom view and cross-sectional view
of the gonio lens with geometric reference constructed in
accordance with a further embodiment of the present invention.
DETAILED DESCRIPTION
Referring now to FIGS. 1A-1C, an embodiment of the gonio lens 10 of
the present invention is housed in a frustoconically shaped shell
12. Housed within the shell 12 is a contact lens element 14, a
minor 16, and a geometric reference member 18.
Referring additionally to FIG. 2, the contact lens element 14 has
an optical axis 20, a concave posterior contact surface 22 that has
a curvature that approximates the curvature of the cornea 24 of an
eye 26 of a patient. The anterior chamber 28 of the eye is defined
between the cornea 24 and the iris 30, and the periphery 32 of the
anterior chamber defines the iridocorneal angle, i.e., the angle
formed by the cornea 24 and the iris 30 of an eye. The trabecular
meshwork 34 is located generally around the base of the cornea
34.
The contact lens element 14 further has an anterior surface 36 that
is offset in an anterior direction from the concave posterior
contact surface 22. The anterior surface 36 may be curved so as to
provide magnification, as shown, or may be plano. The minor 16 is
provided in association with the contact lens element 14, in a
position offset from the optical axis 20 of the contact lens
element 14. The mirror 16 includes a planar surface that is angled
away from the optical axis 20 of the contact lens element 14 as the
planer surface extends in an anterior direction. The mirror 16
receives light rays 38 from the periphery 32 of the anterior
chamber and reflects those rays in a generally anterior direction
toward the observer. As one skilled in the art would appreciate,
the minor 16 having a planar surface may be replaced with any
suitable reflective surface, such as a prism facet. As used herein,
the term minor means any optical surface configured to reflect the
light from the periphery 32 of the anterior chamber 28.
The gonio lens 10 further includes the geometric reference member
18, which in the illustrated embodiment comprises a plurality of
bar-shaped markings arranged along the periphery of a posterior end
40 of the gonio lens 10. The markings are spaced apart from each
other to form a scale. The interval between the markings need not
be constant and may vary to compensate for the curvature of the
posterior end 40 on which the markings are applied. The geometric
reference member 18 may be applied based on any suitable methods,
such as by bonding the geometric reference member 18 to the
radially interior surface of the posterior end 40 or by printing,
painting or etching the markings that form the geometric reference
member 18 on the interior surface of the posterior end 40 or on a
background surface placed on the interior surface. In one
embodiment, varying colors of material (e.g., plastic) may be
laminated together and included in the gonio lens 10 to form the
geometric reference member 18. For example, material (e.g.,
plastic) may be selectively cut away, with the cut-away portion(s)
refilled with pigmented material (e.g., plastic), and included in
the gonio lens 10. As a specific example, the material forming the
contact lens element 14 may be selectively cut away, with the
cut-away portion(s) refilled with pigmented material, such that the
pigmented material (forming the marking(s) of the geometric
reference member 18) remains after the concave posterior contact
surface 22 is created and polished. Cut-away portions may have
different shapes, and different colors (pigments) may be used for
refilling, so as to form geometric reference members having various
marking shapes and/or colors.
In one embodiment, the geometric reference member 18 may be
constructed as a removable component, such as a ring, which is
removably attached to the contact lens element 14 to form the gonio
lens 10. Such a ring may be made of plastic or an elastomer such as
silicone, and may be printed, painted, or etched with the
marking(s) that forms the geometric reference member 18.
FIG. 3 schematically illustrates an image visible to the observer
of the gonio lens 10 of FIG. 2. The observer can see, in addition
to the pupil 42 and the iris 30 of the patient's eye, the periphery
32 of the anterior chamber including the trabecular meshwork 34 and
the related adjacent structures of the eye. FIG. 3 shows a possible
artifact area 44, i.e., a medically problematic area, in the
periphery 32 of the anterior chamber. Using the geometric reference
member 18, the observer can readily determine the size of the
artifact area 44, which ranges between the first marking 18a and
the second marking 18b. The observer can then readily translate the
distance between these two markings into an actual dimension. As
shown in FIG. 3, the field of view of the gonio lens 10 is
preferably at least 45.degree. and possibly about 90.degree., to
permit easy observation of a wide area. The geometric reference
member 18 may be in any suitable color and, preferably, in a color
that is in high contrast to the color of its background 42. The
background 42 may comprise the radially interior surface of the
posterior end 40 of the gonio lens 10 or may be a separate sheet of
material on which the geometric reference member 18 is placed. When
the geometric reference member 18 is in generally white color, the
background 42 is preferably in a bright, non-white color. The
background 42 may comprise fluorescent material that emits light in
a contrasting color relative to the color of the geometric
reference member 18. Alternatively or additionally, the geometric
reference member 18 itself may include fluorescent material that
emits light in a contrasting color relative to the color of the
background 42.
Since the image of the geometric reference member 18 is formed
adjacent to an image of the periphery 32 of the anterior chamber 28
within the field of view of the gonio lens 10, the observer can
readily determine the size or shape of any artifacts in the image
of the periphery 32 of the anterior chamber or the relative
distance between two or more points in such image. The two images
are formed relative to each other (i.e., their respective image
planes being sufficiently aligned relative to each other) such that
the two images are simultaneously in focus to permit the observer
to compare the two images.
FIGS. 4A and 4B illustrate a further embodiment of the gonio lens
10' constructed in accordance with the present invention. The gonio
lens 10' is similar to the gonio lens 10 previously described,
except that it includes a geometric reference member 18' configured
in a generally bar shape. FIG. 5 schematically illustrates an image
visible to the observer of the gonio lens 10' of FIGS. 4A and 4B in
contact with the cornea of a patient's eye. As before, the observer
can compare the image of the periphery 32 of the anterior chamber,
including the trabecular meshwork 34, relative to the image of the
geometric reference member 18', to thereby determine the size or
shape of any artifacts in the image of the periphery 32 of the
anterior chamber or the relative distance between two or more
points in the image. In the illustrated embodiment, the length of
the bar-shaped geometric reference member 18' is chosen so that it
indicates 45.degree. field of view of the gonio lens 10.
FIGS. 6A-6F illustrate still further examples of the geometric
reference member 18 formed in accordance with various exemplary
embodiments of the present invention. FIG. 6A shows a bar-shaped
geometric reference member, similar to the one included in the
gonio lens 10' of FIGS. 4A and 4B. FIG. 6B shows a geometric
reference member comprising a horizontally-arranged series of
vertical bars, similar to those included in geometric reference
member 18 of FIGS. 1A-1C. FIG. 6C shows a geometric reference
member comprising a horizontally-arranged series of horizontal
bars. FIG. 6D illustrates a geometric reference member comprising a
horizontally-arranged series of dots (or circles). FIG. 6E shows a
geometric reference member comprising a rectangular grid. FIG. 6F
shows a geometric reference member comprising a polar grid. All of
these embodiments may function as a scale (e.g., linear scale,
angular scale) to permit geometric measurements of the objects
included in the image of the periphery of the anterior chamber.
FIGS. 7A-7D schematically illustrate an image visible to the
observer of the gonio lens incorporating the geometric reference
members formed in accordance with FIGS. 6C-6F, respectively. As
before, the observer can compare the image of the periphery 32 of
the anterior chamber, including the trabecular meshwork 34,
relative to the image of the respective geometric reference
member.
FIGS. 8A and 8B illustrate yet another embodiment of the gonio lens
10'' constructed in accordance with the present invention. The
gonio lens 10'' is similar to the gonio lens 10 of FIGS. 1A-1C,
except that it includes two minor surfaces 16a and 16b, instead of
one. In operation, the first mirror surface 16a receives light rays
38 from the periphery of the anterior chamber and reflects those
rays toward the second minor surface 16b, which in turn reflects
the received light rays 38 in a generally anterior direction toward
the observer. As before, the mirror surfaces 16a, 16b may be formed
of any optical surface configured to reflect the light from the
periphery of the anterior chamber, such as a prism facet. Also as
before, with the present embodiment, the observer can compare the
image of the periphery of the anterior chamber relative to the
image of the geometric reference member 18, to thereby determine
the size or shape of any artifacts in the image of the periphery of
the anterior chamber or the relative distance between two or more
points in the image.
FIGS. 9A and 9B illustrate a further embodiment of the gonio lens
10a constructed in accordance with the present invention. The gonio
lens 10a is similar to the gonio lens 10 of FIGS. 1A-1C, except
that it does not include any mirror. In operation, the light rays
38 from the periphery of the anterior chamber propagate directly
toward the observer. As before, with the present embodiment, the
observer can compare the image of the periphery of the anterior
chamber relative to the image of the geometric reference member 18,
to thereby determine the size or shape of any artifacts in the
image of the periphery of the anterior chamber or the relative
distance between two or more points in the image.
One of ordinary skill will recognize that the geometric reference
member may be applied in any type of gonio lens, having mirror(s)
or no minors, to view the periphery of the anterior chamber,
including but not limited to, diagnostic lenses and laser lenses
(e.g., SLT goniolaser lenses). One of ordinary skill will also
recognize that the specific configuration of a geometric reference
member may be modified and adjusted depending on the particular
type and purpose of a lens.
While the preferred embodiments of the invention have been
illustrated and described, it will be appreciated that various
changes can be made therein without departing from the spirit and
scope of the invention.
* * * * *